Frank Terjung and Karlheinz M aier Department of physics, Carl von Ossietzky-University Oldenburg, D-26111 Oldenburg, Germany Z. Naturforsch. 53c, 27-32 (1998); received October 9/October 31, 1997 Delayed Fluorescence, Energy Quenching, Pisum sativum , Xanthophyll Cycle Delayed chlorophyll fluorescence decay measurements on the second time scale were ap­ plied to investigate the state of photos...

Introduction of the metallic nanoparticles (NPs) in the bulk glass received a large interest due to their versatile applications. The effect of silver NPs on optical properties of the Eu3+-doped zinc tellurite glasses is presented for the first time. Glass samples are prepared by melt-quenching technique. The surface plasmon absorption bands of silver NPs are recorded in the visible ...

Neural activity during repeated presentations of a sensory stimulus exhibits considerable trial-by-trial variability. Previous studies have reported that trial-by-trial neural variability is reduced (quenched) by the presentation of a stimulus. However, the functional significance and behavioral relevance of variability quenching and the potential physiological mechanisms that may drive it have...

Membrane biofouling is widely acknowledged as the most frequent adverse event in wastewater treatment systems resulting in significant loss of treatment efficiency and economy. Different strategies including physical cleaning and use of antimicrobial chemicals or antibiotics have been tried for reducing membrane biofouling. Such traditional practices are aimed to eradicate biofilms or kill the ...

In Liquid Scintillation Counting (LSC), the scintillating source is part of the measurement system and its detection efficiency varies with the scintillator used, the vial and the volume and the chemistry of the sample. The detection efficiency is generally determined using a quenching curve, describing, for a specific radionuclide, the relationship between a quenching index given by the counte...

The photosystem II (PSII) protein PsbS and the enzyme violaxanthin deepoxidase (VDE) are known to influence the dynamics of energy-dependent quenching (qE), the component of nonphotochemical quenching (NPQ) that allows plants to respond to fast fluctuations in light intensity. Although the absence of PsbS and VDE has been shown to change the amount of quenching, there have not been any measurem...

Previous work on intact thylakoid membranes showed that transient formation of a zeaxanthin radical cation was correlated with regulation of photosynthetic light-harvesting via energy-dependent quenching. A molecular mechanism for such quenching was proposed to involve charge transfer within a chlorophyll-zeaxanthin heterodimer. Using near infrared (880-1100 nm) transient absorption spectroscop...